Running Powervault TL2000 with Ibm LTO4 SAS.  Recently we have run into a problem with large backup jobs over 1TB.  We viewed the error logs and it stated that the drive is bad (Exception F1-01-223 Error Drive is broken).  We sent it out and had it tested and the drive FAILED the IBM ITDT testing.  

We had the drive replaced and we got it in house and ran a few backup jobs with no problem, however, today after 2 days of running over 2TB backups, we have come up with the same error as with our old drive (Exception F1-01 Error_Drive is broken).  

We ran the IBM ITDT test again and passed.  Is there anything else that could cause this error?  Such as corrupted files in the backup job or the TL2000 controller or Power Supply?  Again we had our service people look at it and they said it passes the drive testing and passes all the library tests as well.  They even tested the drive with full write/read test and passes.  They even reflashed the firmware on both the library and the drive but the backups are still creating this error after 2TB.

If anyone has a suggestion, it would be greatly appreciated...